For example, a battery module as a driving source of an electric vehicle is mounted on the electric vehicle running with an electric motor, and a hybrid vehicle running with both an engine and the electric motor. This battery module has a group of single batteries composed of a plurality of arranged single batteries each having electrode terminals. A battery wiring module electrically connects the electrode terminals to each other (for example, see PTL 1).
As shown in FIG. 4, a battery wiring module 101 described in PTL 1 includes a plurality of coupling units 102 coupled in a horizontal direction (an arranging direction of the single batteries). Each coupling unit 102 includes: a bus bar 103 connecting an electrode terminal of one single battery to an electrode terminal of the other single battery adjacent to the one single battery; and a synthetic-resin-made bus bar housing 104 in which the bus bar 103 is housed.
A voltage detection terminal 105 for detecting a voltage of the electrode terminal when connected to the electrode terminal is housed in the bus bar housing 104. The voltage detection terminal 105 includes: a plate-shaped connection portion 150; and a barrel portion 104 extended from the connection portion 150 in an offset shape and connected to a voltage detection line 106.
Further, a barrel portion housing 104A allowing the barrel portion 151 to project forward of the bus bar housing 104 (downward in FIG. 4) is extended forward in substantially the center in a longitudinal direction of the bus bar housing 104. The barrel portion housing 104A is formed in a groove shape opening upward, and the barrel portion 151 is housed in an interior of the barrel portion housing 104A. In the conventional battery wiring module 101, for downsizing the arranging direction of the single batteries in the battery wiring module 101, a pitch between the single batteries adjacent to each other is reduced by extending the barrel portion housing 104A forward of the bus bar housing 104.